Apparatus for unfastening coke oven doors



June 26, .1956

Filed July 7, 1952 F. DOLL APPARATUS FOR UNFASTENING COKE OVEN DOORS 2 Sheets-Sheet l June 26, 1956 F. DOLL 2,752,183

APPARATUS FOR UNFASTENING COKE OVEN DOORS Filed July 7, 1952 2 Sheets-Sheet 2 Fig. 4

f '57 Am TVZL United States Patent APPARATUS FOR UNEASTENING COKE OVEN DOORS Franz Doll, Essen, Germany, assignor, by mesne assignments, to Koppers Company, Inc., Pittsburgh, Pa., a corporation of Delaware Application July 7, 1952, Serial No. 297,433

Claims priority, application Germany July 25, 1951 12 Claims. (Cl. 292-1) The present invention relates to mechanisms for unfastening coke oven doors which are held in the closed position by spring pressure exerted between the closure latches, which engage the door frame or hooks secured thereto, and the door body, such mechanisms becoming operative to release the latch by compression of closure springs by means of fluid pressure operated pressureapplying means adapted to be releasably connected to the door.

Latch mechanisms which utilise closure springs mounted between the body of the door and the closure latches for coke ovens have the advantage that the total closure pressure can be accurately set for each of difierent doors of a battery and can be maintained each time the door of any oven of a battery is remounted in position in its doorway without readiustment of the pressure being necessary on every occasion. To unlatch the coke oven doors it is necessary to compress the springs on the individual doors sufiiciently to enable the latches to be released from their hooks on the door frame. Such compression of the springs, has, in addition to installations where the compression of the springs has been effected by rotation of latch bolts, been carried out by direct axial pressure on the springs axially of the oven chamber, for exampie using pneumaticallyor hydraulically-operated pressure-applying means. The use of compressed air to compress the closure springs for unlatching such doors with the straight-line motion feature of the common assignee in this invention and application and the invention of the copending Patent 2,668,075, provides considerable simplification both of the unfastening means themselves and in the operation of the same, and gives maximum safety as pointed out by the present inventor, as co-inventor of that patent, for this common assignee.

it is an object of the present invention of this common assignee to simplify still further said mechanisms of this nature for unlatching the latch mechanisms of coke oven doors which are equipped with closure springs in accordance with the invention of said Patent No. 2,668,075, of which this present invention and application for patent thereon continues in part by one of the same inventors, Franz Doll, and the common assignee.

Primarily the invention resides in connecting the fluid pressure-applying means to the door body for a coke oven doorway, for example to a spring mounting thereon, by means involving a closed system of forces, hereinafter termed a power-lock, with the patented straight-line motion of said patent for using a coupling such that a thrust is exerted opposite to an opposing pull on the closure springs without the transmission of any counter-thrust through the door or to the frame of the operating machine carrying the unlatching mechanism, in a manner in which it is only necessary to have one fluid pressure operated unlatching mechanism, which operates with the same effect and the same advantages for all the doors of a battery, in contrast to the prior means of this character of the common assignee which heretofore were required on the individual doors for each type of latch mechanism as first embodied in said Patent 2,668,075 of the common assignee of that patent and this copending application.

As has been indicated, because of the closed system of forces which is obtained in using the unlatching mechanism according to the present invention, the high operating pressure applied against the closure springs on the door during unlatching cannot be transmitted to the sensitive door sealing means, nor can the reaction pressure affect the operating machine that carries the unfastening mechanism from door to door. This is of considerable importance inasmuch as the pressure required to compress the closure springs necessarily exceeds the (conventionally 22,00024,0G0 pounds) closure pressure exerted by the springs of the type shown on the drawings when the door is closed. The closed system of forces or power lock ensures the slight compression of the closure springs to take up the locking pressure, which is always the same, once the total pressure has been set.

The pressure on the closure springs to release the latches can, in an unfastening mechanism according to this invention, be produced by any suitable device, for example, by means of a screw threaded spindle, a rack and gearing, or like means, preferably with the screw spindle, however, in conjunction with the straight-line motion of a pneumaticallyor hydraulically-operated pressure-applying means as is employed in said patent.

According to a further feature of the invention, such fluid pressure operated means preferably comprises a fluid pressure chamber formed by an expansible envelope of rubber, Buna or the like. It may, however, comprise a multi-folded metallic capsule which is adapted to be expanded under the action of the fiuid pressure medium (e. g. air or liquid).

The unlatching means according to the present invention, may, moreover, be arranged on a framework which is adapted to be propelled along either side of the coke oven battery. Advantageously, however, such unlatching means may be connected to the door-handling gear which is operable to insert or withdraw the door from the coke oven chamber, which in turn is generally connected on the pusher machine side of the oven battery with the pusher machine, and on the coke side of the battery with the coke guide car.

The coupling of the power locked unlatching mechanism with the door latches can be effected by any appropriately-formed coupling device. In accordance with a further feature of the invention the coupling is preferably carried into effect by means of claws which, when the unlatching mechanism is applied against the latch on an oven door, are automatically engaged in the required power lock condition with the latch mechanism as a result of the motion of spotting the unlatching mechanism and/or under the influence of the fluid pressure medium in its chamber.

A further feature of the invention resides in suspending the fluid pressure operated unlatching mechanism from the door-handling gear, as from the framework for its movement from oven to oven, by means of springs in cardan joint fashion. By this means it is possible, if the coupling end of the unlatching mechanism is of suitable form, to bring the unlatching mechanism into proper engagement with the door latch mechanism even if the two parts are not accurately centred.

In one form of the invention the power lock between the unlatching mechanism and the door body, when the latter is latched, is obtained by pivoted coupling claws of bellcrank form which, when the unlatching mechanism has been shifted up against the latch mechanism of the door, automatically engage the latter under the action of the fluid pressure medium supplied to the fluid pressure- =3 applying means, such that the pressure exerted by the pressure medium can only be imparted to the closure springs and not to the door seal and doorway. There is even less likelihood of the reaction pressure being transmitted to the framework of the gear for transporting the unlatching mechanism, for example the door-operating gear that moves from oven to oven. The unlatching mechanism is, moreover, so constructed in this embodiment that, after the claws have graspingly engaged a keeper on the latch mechanism, a thrust pressure is exerted in the opposite direction on the closure springs by a thrust member under the action of the fluid pressure medium introduced into the pressure chamber for the pressure-applying means, and a pull is thus simultaneously exerted by the claws on the latch springs opposite the thrust on the springs, thereby positively ensuring the required power-locked connection. 7

In the case of latch mechanisms in which the closure springs are arranged to be compressed, when the door is to be unfastened, by means of a bolt carrying-the latch or by means of a nut arranged thereon, the present invention may for example be carried into effect as in Figs. 1 to 3, by pivotally mounting the coupling claws at their apexes to a carrier for the unlatching mechanism which carrier is connected to the framework of the operating machine that moves from oven to oven. In this event, one limb of each of the coupling claws is arranged to move in and out between a part of the housing defining the fluid pressure chamber and a thrust element subject to the pressure of a spring which permits an axial displacement of the fluid chamber and claw part of the unlatching mechanism relative to the framework machine that moves from oven to oven and also relative to the latch. With this arrangement, when the unlatching mechanism has been moved up against the latch mechanism, the other limb of each claw then engages the door latch under the pressure of the yielding movement of the pressure chamber relative to the framework machine.

If the latch bolt is firmly mounted on the door body so that the closure springs are compressed directly, or through a bushing in the latch, in accordance with a further constructional feature of the present invention, as in Figs. 4 to 6, a pressure head of the housing or casing of the fluid pressure chamber is firmly connected to the machine that moves from oven to oven through cardanmounted springs and with a movably mounted shaft. Grasping means in the form of coupling claws are pivotally mounted at the inner end of the shaft and may be provided with lugs or projections such that by pressing these latter against a latch bolt secured on the door body, the coupling claws are moved about their pivots to engage behind a collar or projections forming keeper means on the latch bolt to pull on the same, whilst a thrust ring or the like acting to exert a thrust in the opposite direction against the closure springs, is arranged on another pressure head of the housing or fluid pressure casing.

Projections or the like, which may be spring-pressed, are arranged on the thrust ring to abut the grasping claws into engagement with the keeper, and to abut, on interruption of the supply of pressure medium, against projections or the like arranged on the coupling claws, thereby to release these latter from the keeper means on the latch bolt.

The pressure heads are oppositely movable and the shaft having the claws projects through the head having the thrust member with the latter surrounding the claws and the pressure for effecting the compression of the closure springs can, in this instance, be produced by a pistoneylinder assembly or by an envelope of resilient material (e. g. rubber, Buna or the like). The pressure chamber can, for example, instead be constituted by a multifolded sheet metal capsule.

In accordance with yet another feature of this arrangement, the pressure head part of the housing or casing of the fluid pressure chamber which acts against the keeper of latch mechanism is furnished with the shaft having said claws, which shaft is coaxial with the oven chamber, and the other pressure head part the unlatching mechanism is displaceably mounted thereon for acting oppositely thereto on the latch spring.

Furthermore, this shaft may be provided at its end opposite the grasping elements with .an adjustable stop nut by which the unlatching mechanism is connected as a unitary whole cardan-fashion, and under spring pressure, in angularly adjustable condition with the framework that moves the unit from oven to oven.

Embodiments suitable for carrying the invention into efiect are illustrated by way of two examples in the accompanying drawings in which:

Figure 1 illustrates the firstform of unlatching device according to the invention, in a condition prior to the engagement of the door latching device with a coke oven door latch.

Figure 2 illustrates the same mechanism in position after the door latching device has been brought up and engaged the latch, but before the fluid pressure medium is supplied thereto Figure 3 illustrates the parts of the same arrangement after the pressure medium has been introduced.

Figure 4 illustrates a second, and the preferred, embodiment of the invention in a condition, like in Figure 1, prior to the engagement of the door-latching device with a coke oven door latch on a coke oven door body.

Figure 5 illustrates the same mechanism in position after the door-latching device has been brought up and engaged the latch but before the fluid-pressure medium is supplied thereto for grasping.

Figure 6 illustrates the parts of the same arrangement after the pressure medium has been introduced with the device in grasping relation.

'Similar parts have been indicated with the same reference characters throughout the drawings.

In both embodiments, the basic feature of the invention of said Patent 2,668,075 of February 2, 1954, filed November 16, 1951, is continued, that is, as stated in lines 41 to 52 of column 2 of said patent, the fluid pressure operation of the springs, which exert the sealing pressure on the gas seals, is effected by means of a compression device comprising a fluid pressure chamber and a thrust member extending directly between the fluid pressure chamber and the spring means and movable by fluid pressure in a straight-line motion, to provide both simplicity and economy of fluid pressure operation and faster closing and opening of the doors, with flexibility of sealing pressure on the seals.

The coke oven door, which has not been illustrated in any detail, is designated 1. The reference numeral} indicates the operating machine or carriage framework, for

example the door handling gear, which carries the unlatching mechanism from oven to oven of the coke oven battery. The term door handling gear is to be interpreted as including both the coke pusher machine on the pusher side and also the coke receiving car on the coke side of the oven battery.

A spring bearing housing 7, in which the door closure springs 8 are located, is rigidly connected to the door 1 by means of a plate 3. Pivotally mounted on a latch bolt 5, which passes through the spring bearing housing 7 is a latch 6, the two side arms of which are located behind hooks (not shown) connected to the door frame, in theclosedcondition of the door. The spring 8 is a compression spring and is mounted in a housing 7 which, on pressing of the spring against the latch 6 exerts pressure against plate 3 to produce the sealing pressure when the door 1 is, closed.

The unlatching mechanism as a whole is connected cardan-joint fashion to the door operating gear carriage 2 by a plurality of spaced apart springs 10 whereby the unlatching' mechanism is mounted for displacement as a 3 unitary whole relative to the door 1 and to the operating carriage.

Referring now more partZcularly to the embodiment illustrated in Figures 1 to 3, lateral spaced brackets 11 are connected at top and bottom to bell crank levers 13 by pivots at their apices 12. One arm 14 of each bell crank 13 has a pin 15 disposed between a thrust element 16 and one pressure head 17 of a pair for a fluid pressure housing or casing 26. The other pressure head 13 of this housing or casing 26 constitutes with the casing part 26 and head 17 a pressure chamber 19, to which pressure medium can be supplied at 20, between the two heads 17 and 18. In this embodiment, the head 17 and casing 26 may be fixed relative to each other, as by welding, so as to slide as a unit relative to head 18.

The pressure head 18 or" the pressure housing carries a shaft 21 on which are displaceably mounted the other pressure head 17 of the housing, the thrust element 16 and the carrier 9 for brackets 11. The end of shaft 21 is threaded adjacent carrier 9 and carries an adjustable stop nut 22 against which the carrier 9 is adapted to be applied by the pressure of a spring 23 arranged between this plate 9 and the thrust element 16. The pressure chamber 19 is lined by an expansible, annular hollow body 24 in the form of an envelope, for example of Buna. The envelope 24 is firmly clamped at one region in chamber 19, as by securing it at its outer margin between the pressure head part 17 and an inwardly-directed flange of the casing 26, with the interposition of a metallic ring 25. The pressure head part 18 is displaceably mounted relatively to these parts so that the two heads 17, 18, are each oppositely movable, and movable relative to each other in opposite directions in res ect of the chamber 19 therebetween.

The other end of each bell crank lever 13 carries a pin 27 which interconnect, on operation thereof by bell crank levers mounted on the laterally spaced brackets 11 of the carrier 9, in such a way that (as is observed from Figures 2 and 3) these connecting pins 27 engage in the annular space 28 between the spring bearing housing 7 and the attachment plate 3 of the latch mechanism.

As is seen from Figure 2, the connecting pins 27 of the bell crank levers 13, which act as claws or grasping elements, enter the interspace 28 when the unlatching mechanism is advanced as a whole toward the body of the door 1. At the same time a conical recess 29 of the pressure head part 18 is applied against the head end 30 of the latch mechanism bolt 5. By virtue of the conical recess 29 and the cardan suspension of the unlatching mechanism as a whole on the door operating carriage 2, as provided by the springs 19, the unlatching mechanism always adjusts itself, despite any small misalignment of the shaft 21, to the head end 30 of the latch bolt 5 so that correct engagement is guaranteed. The advance of the unlatching mechanism towards the door 1 causes the carrier 9 for brackets 11 to be pushed along the shaft 21 against the pressure of spring 23 until the pins 27 of the claws 13 engage in the annular space 28 of the latch mechanism by reason of the forward movement of the pivots 12 of these claws and the rearward movement of head 17 against pins when head 18 is arrested by the head end 39 of bolt 5. This condition is clearly seen in Figure 2 in which the pins 15 have rotated claws 13 on their pivots 12.

Pressure medium (e. g. compressed air) is now admitted to the interior'of the elastic hollow body 19 through duct at a pressure suflicient to compress the springs 8 the amount required for release of the latch 6. At this time, as can be seen from Figure 3, the pressure part 18 of the housing 26 is pressed against the head end of the latch bolt 5, whereby the pressure head parts 18, 17 are forced somewhat apart with head 18 away from its position in outer alignment with the outer part of the inwardly directed flange of casing 26 as illustrated in Figures 1 and 2. Furthermore the pressure exerted through the pressure head part 17 on the pins 15 of the arms 14 of the bell crank claws 13 ensures that these claws cannot be released from their power locked engagement with the bearing housing 7 for spring 8, which has bolt 5 axially movable to and from plate 3.

When the heads 17, 18 move oppositely with at least one head 17 or 18 moving away from the other, claws 13 pull on housing 7, and head 17 pushes on the latch bolt 5, thus taking off the closure pressure, and only then can the latch 6 be swung away from its hooks, the unlatching mechanism withdrawn and the door removed from the oven chamber. When the door is reinserted in its opening it can be latched in a corresponding fashion.

The embodiment of the invention in Figures 4 to 6 is preferred for unlatching the latch mechanisms of doors in which the latch bolt 5 is rigid with the door body 1, i. e. is not axially displaceable axially of the oven chamber closed by door 1. Thus, in this instance the compression of the closure springs 8 must therefore either be efi'ected by direct pressure on a thrust ring 31, arranged between the closure springs 8 and the latch 6, or by pressure on this ring 31 through a bushing 32 by which the latch 6 is rockably mounted on the axial bolt supporting member 5.

In this embodiment the pressure head part 17 of the fluid pressure chamber housing 26 is displaceable relative to casing 26 and head 18, and casing 26 may be integral, as by welding, with head 18, and the head 17 is directly connected to the supporting carrier means, i. e. the door handling machine 2, in cardan-joint fashion by the springs 10. As in the case of Figs. 1 to 3, the pressure chamber 19 is lined by an expansible annular body 24 in the form of an envelope, for example Buna. The envelope is firmly clamped at one region in chamber 19, as by securing it at its outer margin between the pressure head part 18 and the inwardly directed flange of the casing 26, with the interposition of a metallic ring 25. The clamping is done between head 18, instead of head 17 as in Figs. 1 to 3, and the flange of casing 26 to permit the head 17 to be displaceable relative to all parts, as shown in Figs. 4 to 6. The other pressure head part 18 of the pressure chamber 19 has a forwardly projecting thrust cylinder 33 which may be composed of separate arms and which can be forced against the latch bushing 32. The head 17 of the pressure chamber housing 26 is rigidly connected to the shaft 21 by a nut 34 screwed up on the shaft, with an interposed washer 35, and the other end 36 0f the shaft 21 is formed as a collar, the shoulder of which bears against the head part 17.

Screwed into the outer end of the shaft 21, i. e. the end furnished with the nut 34, is a bolt 38 which is formed with a conical head 37 and which passes through the wall of the supporting carrier means 2 in such a way as not to interfere with a cardan-type movement of the unlatching mechanism as a whole for the purpose of making proper alignment engagement with the latch bolt 5 of the door 1 even when the unfastening device as a whole is not accurately centered.

The pulling claw levers 13 are mounted in pivot bearings 39 at the inner end 36 of shaft 21, these claw levers consisting of two substantially semi-circular grasping parts which are bent over hook fashion at their ends. The coupling claw levers 13 are provided, in the vicinity of their pivots, with inwardly-directed lugs 40 adapted to be pressed against the head end 30 of the latch pin or bolt 5, or against a nut screwed on this head.

As will be observed from Figure 5, the shaft portion 36 projects axially through the pressure head 18 which also surrounds the claws 13 which are so constructed and of such length that, when the lugs 40 of these claws abut against the head 30 of the latch bolt, the claws first of all have a small clearance from the peripheral keeper edge 41 of the latch bolt 5 when the claws are pivoted into the position illustrated. When the claws 13 have reached this position, compressed air is supplied to the pressure chamber 19. As a result the surrounding cylindricalthrust member or projection 33 is forced forwardly against the latch bushing 32, and, consequently, against the closure springs '8, whilst the pressure which is exerted at the same time on the head part 17 produces a counterefiect pull on the claws 13 so that these bear in the opposite direction against the collar or keeper 41 of the latch bolt 5. Thus no pressure can be transmitted to the carrier means 2 for the door unlatching mechanism nor to the doorframe around the door body 1, since a power lock is set up. The backward movement of the claws 13 to the position where they abut against the surface of keeper collar 41 effects compression of the cardan springs and a spring 42 arranged on the shaft 21 between a collar 43 of the pressure head part 18 and a corresponding collar 44 on the end of the shaft 21. This condition is illustrated in Figure 6 in which position the springs 42 are compressed, and so can later expand to move the two pressure heads towards each other, thus moving the claws 13 and thrust member 33 apart, upon release of fluid pressure from chamber 19.

Located on the inside of the thrust cylindrical thrust member or projection 33 of the pressure head part 18 in the vicinity of claws 13 are projections which may as in the case illustrated, comprise screw bolts 45 which pass through the wall of this projection 33. These screw bolts 45 project a suflicient distance inwards toward claws 13 as to be applied, in the coupled condition, against the outer walls of the coupling grasp claws 13 and thereby prevent an outward disengaging movement of the claws from the keeper means 41.

Projections 46 are also rigidly furnished on the coupling claws 13 in the path of the bolts 45, and the ends of the screw bolts 45 abut against these projections 46 when the claws 13 are to be released on interruption of the compressed air supply to the housing chamber 1%, Whereby the coupling claws 13 are moved on their pivots out of interlocked engagement with the keeper collar 41 of the latch bolt 5. The pressure of the bolts 45 against the projections 46 is produced by the expansion of the closure springs 8 when the compressed air supply is cut OE and is augmented by the expansion of spring 42 of the shaft 21 which reapplies the head part 18 and its collar 43 against the head part 17 as is apparent from Figure 1.

Two latch mechanisms are, in the usual fashion, furnished on each oven door 1, one being arranged at the upper and the other at the lower part of the door 1. When the door is latched it is of advantage first to operate the lower latch mechanism for bar 6 and thus seal the lower part of the door, and thereupon deal with the upper part. In the case of the apparatus according to this invention this may conveniently be carried into effect by incorporating a pressure delay valve in the pressure medium line leading to the chambers 19 of the two unlatching mechanisms, whereby the lower latch bar 6 is operated first, and thereafter the upper latching bar 6.

Subject matter disclosed but not claimed herein, is the subject of the same inventors copending application Serial No. 574,330, filed March 27, 1956, entitled Apparatus for Unfastening Coke Oven Doors.

What I claim is:

1. Fastener apparatus for unfastening coke oven door latches slidably mounted on a support axially of a doorway, and provided with a spring member for exerting the total closure pressure between the latch and a door to be latched thereby, with the axial support provided with an element for exerting a pull on the spring member and keeper means for coaction with grasping means for transmitting a pulling force to the spring member through the axial support for the latch, comprising: two oppositely movable fluid pressure responsive reciprocable pressure heads and a fluid pressure casing providing a fluid pressure chamber within the same between the heads, a spring cardan joint structure supporting the apparatus as a single unitary whole, a shaft rigidly secured axially to one of said pressure heads and slidably extending axial- 1y through the other of said two pressure heads, g asping elements pivotably mounted on the end of said shaft at a region beyond the other pressure head where the slidable shaft projects out of the same for coupling connec-- tion with keeper means on the axial supports for said latches, said grasping elements also having an abuttingelement in position to turn the grasping elements about their pivotinto grasping engagement with a said keeper means when the unitary whole is pressed up against a said axial support for a latch on a coke oven door, and said other pressure head having thrust member in position thereon for exerting an opposing thrust on the spring member for a said latch when the grasping means is in operative engagement with an axial support for a said latch for exerting a pull thereon.

2. Fastener apparatus as claimed in claim 1 and further characterized by cooperating abutting members on the thrust member and on the grasping means operable, respectively, and cooperable on retraction of the thrust member to disengage the grasping means from coupling relation with a keeper means on a said axial support for a latch.

3. Fastener apparatus as claimed in claim 2 and which includes retracting means for exerting a retracting pressure on the thrust member.

4. Fastener apparatus as claimed in claim 3, and in which the retracting means comprises spring means interposed between, and normally urging apart, the head for the thrust member and the pivotal portion of the grasping means on the shaft of the other pressure head.

5. Fastener apparatus as claimed in claim 3, and in which the abutting member on the thrust member is in position thereon to engage another part of the grasping means to ensure retention of the latter means onthe keeper, when the pressure heads are under pressure of fluid in the chamber between.

6. Fastener apparatus for unfastening coke oven door latches slidably mounted on a support axially of a doorway, and provided with a spring member for exerting the total closure pressure between the latch and a door to be latched thereby, with the axial support provided with an element for exerting a pull on the spring member and keeper means for coaction with grasping means for transmitting a pulling force to the spring member through the axial support for the latch, comprising: two oppositely movable fluid pressure responsive reciprocable pressure heads and a fluid pressure casing providing a fluid pressure chamber within the same between the heads, a spring cardan joint structure supporting the apparatus as a single unitary whole, a shaft rigidly secured axially to one of said pressure heads and slidably extending axially through the other of said two pressure heads, grasping elements pivotably mounted on the end of said shaft at a region beyond the other pressure head where the slidable shaft projects out of the same for coupling connection with keeper means on the axial supports for said latches as aforesaid, and a thrust member arranged in surrounding relation to said grasping means and having a part in position thereon to engage another part of the grasping means to compress the grasping means into, and retain the same in, grasping relation with the keeper on a said axial support for a latch on a coke oven door, When the pressure heads are under pressure of fluid in the chamber between them.

7. Fastener apparatus as claimed in claim 6, and which includes retracting means for exerting retracting pressure on the thrust member, to disengage the coupling from a latch.

8. A coke oven door latching mechanism comprising the combination of latch parts comprising a door latch for securing the coke oven door which latch is movable relative to the door for securing and releasing the door, a spring normally urging the latch and door apart from 'each other for effecting the securing pressure, and a support for the spring on the exterior of the door for supporting the spring on the outside of the door in position to effect pressure movement of the latch and door in opposite directions from each other to secure them in place; and a fluid pressure-operated compression device at the exterior of the door and operable on the spring means to relieve the latch of such spring pressure for release of the door from latching pressure relation with the latch, said compression device comprising a fluid pressure chamber and a thrust member extending directly between the fluid pressure chamber and the spring means and movable by fluid pressure in said chamber in a strai ht line motion, said thrust member comprising an attachable set of two oppositely acting latch part engaging members at least one of which is movable in a to and fro movement relative to the other for releasable connection of the compression device to the latch parts to compress the spring means thereof for releasing the latch of its fastening pressure engagement, said fluid pressure chamber comprising a set of two opposite chamber members responsive to fluid pressure in the chamber and connected to the latch part engaging members respectively with at least one of the chamber members movable with a to and fro movement relative to the other for setting up opposing forces in unison between the latch part engaging members, said set of latch part engaging members being engageable oppositely to grasp with a part of the latch on the door and to exert a thrust on another part of the latch in power-locked fashion, under the pressure operation efiect of the chamber members, to transmit a thrust to the latch closure spring means and impose a corresponding counter thrust thereon in a closed path, in releasing the latch of its fastening pressure engagement.

9. A coke oven door latching mechanism comprising the combination of door latch parts comprising a door latch for securing the coke oven door which latch is movable relative to the door for securing and releasing the door, a spring normally urging the latch and door apart from each other for eflecting the securing pressure, and a support for the spring on the exterior of the door for supporting the spring on the outside of the door in position to effect pressure movement of the latch and the door in opposite directions from each other to secure them in place; and a fluid pressure-operated compression device at the exterior of the door and operable on the spring means to relieve the latch of such spring pressure for release of the door, said compression device comprising a fluid pressure chamber and a thrust member extending directly between the fluid pressure chamber and the spring means and movable by fluid pressure in said chamber in a straight line motion, said thrust member comprising a coupling device in the form of an attachable set of oppositely acting latch part engaging members for releasable connection of the compression device to the spring means for releasing the latch of its fastening pressure engagement, said fluid-pressure chamber comprising a set of opposite working faces responsive to fluid pressure in said chamber and connected to the oppositely acting latch part engaging members, respectively, for setting up opposite forces therebetween in unison, said set of oppositely acting latch part engaging members being engageable one to grasp with a part of the latch on the door and the other to exert a thrust on another part of the latch in power-locked fashion, under the op posit: fluid pressure operation effect of the opposite working faces of the fluid pressure chamber, to transmit a thrust to the latch closure spring means and impose a corresponding counter thrust thereon in a closed path in releasing the latch of its fastening pressure engagement, one of the latch part engaging members being mounted for relative movement in relation to the remainder of the fluid compression device as a whole, to be moved toward and away from the other latch part engaging member, for effecting its engagement with its latch part, and means operable by the other latch part engaging member for automatically urging and maintaining the aforesaid relatively movable latch part engaging member, in engagement with its latch part upon admission of fluid pressure medium to the fluid chamber.

10. A closure fastener as claimed in claim 9, and in which the fluid pressure chamber comprises an expansible envelope.

11. A closure fastener as claimed in claim 9, and which includes a carrier-supporting element for supporting the entire compression device for movement as a unitary whole into and out of operative relation with the said latch parts, and cardan joint spring means for yieldably supporting the carrier-supporting element from carriage means therefor.

12. Fastener apparatus as claimed in claim 11, and further characterized by one of the latch part engaging members comprising claws with means thereon for automatically moving the member into, and maintaining it in, grasping relation with the latchpart of the door in said power-locked fashion in response to the dual action of the advancing of the compression device up into contact with the door latch and the movement of the oppositely acting Working faces of the fluid chamber member upon admission of fluid pressure medium to the fluid chamber.

References Cited in the file of this patent UNITED STATES PATENTS 2,109,740 Carlborg Mar. 1, 1938 2,190,297 Salkvist Feb, 13, 1940 2,216,433 OConner Oct. 1, 1940 2,367,776 Hollerith Jan. 23, 1945 2,622,315 Loveland Dec. 23, 1952 

1. FASTENER APPARATUS FOR UNFASTENING COKE OVEN DOOR LATCHES SLIDABLY MOUNTED ON A SUPPORT AXIALLY OF A DOORWAY, AND PROVIDED WITH A SPRING MEMBER FOR EXERTING THE TOTAL CLOSURE PRESSURE BETWEEN THE LATCH AND A DOOR TO BE LATCHED THEREBY, WITH THE AXIAL SUPPORT PROVIDED WITH AN ELEMENT FOR EXERTING A PULL ON THE SPRING MEMBER AND KEEPER MEANS FOR COATION WITH GRASPING MEANS FOR TRANSMITTING A PULLING FORCE TO THE SPRING MEMBER THROUGH THE AXIAL SUPPORT FOR THE LATCH, COMPRISING: TWO OPPOSITELY MOVABLE FLUID PRESSURE RESPONSIVE RECIPROCABLE PRESSURE HEADS AND A FLUID PRESSURE CASING PROVIDING A FLUID PRESSURE CHAMBER WITHIN THE SAME BETWEEN THE HEADS, A SPRING CARDAN JOINT STRUCTURE SUPPORTING THE APPARATUS AS A SINGLE UNITARY WHOLE, A SHAFT RIGIDLY SECURED AXIALLY TO ONE OF SAID PRESSURE HEADS AND SLIDABLY EXTENDING AXIALLY THROUGH THE OTHER OF SAID TWO PRESSURE HEADS, GRASPING ELEMENTS PIVOTABLY MOUNTED ON THE END OF SAID SHAFT AT A REGION BEYOND THE OTHER PRESSURE HEAD WHERE THE SLIDABLE SHAFT PROJECTS OUT OF THE SAME FOR COUPLING CONNECTION WITH KEEPER MEANS ON THE AXIAL SUPPORTS FOR SAID LATCHES, SAID GRASPING ELEMENTS ALSO HAVING AN ABUTTING ELEMENT IN POSITION TO TURN THE GRASPING ELEMENTS ABOUT THEIR PIVOT INTO GRASPING ENGAGEMENT WITH A SAID KEEPER MEANS WHEN THE UNITARY WHOLE IS PRESSED UP AGAINST A SAID AXIAL SUPPORT FOR A LATCH ON A COKE OVEN DOOR, AND SAID OTHER PRESSURE HEAD HAVING THRUST MEMBER IN POSITION THEREON FOR EXERTING AN OPPOSING THRUST ON THE SPRING MEMBER FOR A SAID LATCH WHEN THE GRASPING MEANS IS IN OPERATIVE ENGAGEMENT WITH AN AXIAL SUPPORT FOR A SAID LATCH FOR EXTERING A PULL THEREON. 